If you had to snog your mum for 30 secs every night then you would eventually get into a habit of it and it would become just a normal part of your day - I'd say that after the first year or so 99% of the time it would be completely non-sexual and you'd both just have a quick snog, maybe a fumble, and then get off to sleep. Your mum could be annexed into a granny flat and just pop round for the evening snog, which remember is only going to last 30 seconds.

BUT imagine the massive pain in the arse of having to take a step backwards with every two forwards - You'd have to leave so much more time to get anywhere, and it'd be so frustrating if you were in a rush for anything - If you were running towards the fast-closing doors of a train, knowing that if you ran straight for it you'd just catch it, but with every two bounds forward you run, you have to stop and take a full step back - you'd miss the train mate, not even taking into account how much of a stupid prick you'd look.